Work is now underway to develop microfluidic devices for analyzing chemical or biological fluids. A xe2x80x9cmicrofluidicxe2x80x9d device typically includes fluid channels having microscale dimensions. For example, a fluid channel in a typical microfluidic device may have a width of less than about 1000 microns.
In a typical application for a microfluidic device, a fluid containing a chemical compound may flow towards a reaction site on the microfluidic device. At the reaction site, the fluid may contact another fluid containing a different substance. The characteristics of the resulting fluid passing downstream of the reaction site may be detected to determine if the chemical compound reacts with the substance. The characteristics of the fluid may correspond to, for example, the concentration of the chemical compound in the fluid stream. If the concentration of the chemical compound in the fluid passing downstream of the reaction site is lower than the concentration of the chemical compound upstream of the reaction site, then it is likely that the chemical compound reacts with the substance.
Microfluidic analytical systems have a number of advantages over other types of analytical systems. For example, microfluidic systems are particularly well suited for analyzing or reacting samples with low volumes. In a typical microfluidic system, samples on the order of nanoliters or even picoliters can be reacted or analyzed. Because of the small volumes of fluids being handled, microfluidic analytical systems may be used to rapidly assay large numbers of samples. The assays can be performed to study the effect of numerous compounds in various biological processes. For example, test compounds that may block, reduce, or enhance the interactions between different biological molecules, such as a receptor molecule and a corresponding ligand, may be identified as potential candidate drugs.
In recent years, the number of test compounds produced by modern combinatorial chemistry techniques has dramatically increased. While conventional microfluidic systems can be used to test the increasing number of compounds, the throughput of such systems could be improved. There is a continuing need to screen large numbers of samples quickly and accurately.
Embodiments of the invention address this and other problems.
Embodiments of the invention can be used to quickly detect the characteristics of fluids in a microdevice. Embodiments of the invention can be used for, for example, high-throughput drug candidate screening and medical diagnostics.
One embodiment of the invention is directed to a microdevice for supporting a flowing fluid. The microdevice comprises: a substrate; and a pair of generally parallel, spaced wall members on the substrate, wherein at least one of the wall members includes a pair of structures defining an opening.
Another embodiment of the invention may be directed to a microdevice comprising: a substrate; a plurality of wall members; and a plurality of fluid channels, wherein each of the fluid channels is defined by adjacent wall members in the plurality of wall members, wherein each wall member comprises an opening that is formed by opposed beveled structures of the wall member and that communicates the adjacent fluid channels.
Another embodiment of the invention is directed to a method for detecting a characteristic of a fluid, the method comprising: (a) inserting a probe into a fluid channel in a microdevice; (b) detecting a characteristic of a first fluid flowing in the first fluid channel; (c) moving the probe from the first fluid channel through an opening in one of the walls defining the first fluid channel and to a second fluid channel adjacent to the first fluid channel; and (d) detecting a characteristic of a second fluid flowing through the second fluid channel.
Another embodiment of the invention is directed to an analytical assembly comprising: a detection assembly comprising a plurality of detection devices; and a microdevice comprising a plurality of wall members and a plurality of fluid channels, wherein each of the fluid channels is defined by adjacent wall members in the plurality of wall members.
Another embodiment of the invention is directed to a method for detecting a characteristic of a fluid, the method comprising: flowing a plurality of different fluids through respective fluid channels in a microdevice, each of the fluid channels in the microdevice being formed by adjacent pairs of wall members; and detecting characteristics of the plurality of different fluids substantially simultaneously using a plurality of detection devices as the different fluids flow through their respective fluid channels.
These and other embodiments of the invention are described in further detail with reference to the Figures and the Detailed Description.